SIST I-ETS 300 763-2 E1:2003

• Abstract:

  To specify the abstract test suite for conformance testing of in-band signalling of an ISDN videotelephony terminal which uses one or two B-channels as specified in ETS 300 143, ETS 300 144 and ETS 300 145

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• ICS: 33.160.60 - Multimedia systems and teleconferencing equipment
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Mandate: T-294
• Ref Project: ETSI I-ETS 300 763-2 ed.1 (1997-08) - Integrated Services Digital Network (ISDN); Audiovisual services in-band signalling testing; Part 2: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification

SIST I-ETS 300 763-2 E1:2003 is a Slovenian standard identical to ETSI I-ETS 300 763-2 Edition 1. It specifies the Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma for conformance testing of in-band signalling in Integrated Services Digital Network (ISDN) videotelephony terminals. The scope is terminals using one or two B-channels, with the test basis taken from ETS 300 143 and ETS 300 144.

What does SIST I-ETS 300 763-2 E1:2003 specify?

SIST I-ETS 300 763-2 E1:2003 specifies the abstract conformance tests for ISDN videotelephony in-band signalling, together with the PIXIT questions needed to run those tests. The document is structured as five clauses plus three annexes, so a reader can move from scope and definitions to the actual test organization and supporting proformas.

Annex	What it covers
Annex A	Partial PIXIT proforma with questions for the implementation under test
Annex B	Abstract Test Suite in TTCN graphical form and TTCN machine-processable form
Annex C	Bibliography

The scope includes conformance testing of an ISDN Videotelephony terminal that uses one or two B-channels and implements the frame structure and syntax of ETS 300 144 together with the in-band signalling procedures of ETS 300 143. The document also states that no testing of data commands or applications is included among the tests, and that restricted network operation is outside the scope.

What are the key requirements of SIST I-ETS 300 763-2 E1:2003?

The most important technical content is the test method, the way BAS traffic is handled, and the way test cases are grouped and named. These points matter because they determine how a test tool must drive the terminal and what information the implementer must provide in the PIXIT.

• Clause 4.1 uses a multiparty, concurrent testing method with one Master Test Component (MTC) and three Parallel Test Components (PTCs), one for the D-channel and one for each B-channel. In practice, this means the test platform must control call setup and observe channel behaviour in parallel.

• Clause 4.1.1 defines the start-up sequence between the MTC and the PTCs and allows the MTC and D-channel PTC to be combined if needed. The document keeps the event order fixed, so tool-specific scripting must not change the sequence of test events.

• Clause 4.3.1 and 4.3.2 define a filter for received Bit rate Allocation Signal (BAS) codes. Repeated BAS command sets are treated as a single set until something changes, which keeps the test script from being overloaded with repeated signalling and ensures that only meaningful changes reach the ATS.

• Clause 4.3.3 defines how transmitted BAS events are handled. When a cap set or command group is sent, it continues as specified until another event replaces it, so the tester knows how long a signalling state is meant to persist.

• Clause 4.4 gives the naming convention for test cases, variables, timers, parameters, and BAS constraints. This matters because the numbering links each test case back to its test purpose, and the naming rules make scripts, logs, and PIXIT items easier to map.

• Clause 4.5 says the ATS does not specify audio or video content tests, but the test tool should send audio, video, and data that match the BAS commands under test. In practice, this avoids Mode Mismatch procedures that could stop a test before the signalling behaviour is exercised.

• Clause 4.6 limits D-channel detail to the required action, usually establishing or clearing a B-channel. That keeps the ATS focused on in-band signalling while allowing different D-channel implementations, as long as they achieve the same control action.

• Clause 5 splits the ATS into single-channel communication and two-channel communication test groups. Many two-channel behaviours are first exercised in single-channel operation, which reduces duplication and helps validate shared signalling behaviour before the second channel is added.

What terms does SIST I-ETS 300 763-2 E1:2003 define?

• Abstract Test Suite (ATS): the set of abstract test cases that define what must be exercised and observed for conformance testing.
• Protocol Implementation eXtra Information for Testing (PIXIT): implementation-specific information that the test laboratory needs before executing the ATS.
• Implementation Under Test (IUT): the terminal or implementation being checked by the test system.
• Master Test Component (MTC): the controller that schedules the test components and coordinates the overall execution.
• Parallel Test Component (PTC): a test component that handles a specific channel or role in the concurrent test setup.
• Point of Control and Observation (PCO): the place where the IUT’s behaviour is observed and controlled by the test script.
• Bit rate Allocation Signal (BAS): the signalling code used in the frame to carry commands, control, and indication information.

Who uses SIST I-ETS 300 763-2 E1:2003?

SIST I-ETS 300 763-2 E1:2003 is used by conformance test laboratories, terminal manufacturers, and test tool developers working on ISDN videotelephony. Test labs use it to build TTCN-based conformance tests and to prepare the PIXIT questionnaire for an implementation under test. Manufacturers use it to verify in-band signalling on one or two B-channels, while quality managers and buyers can use it to check whether a terminal is intended for the ETS 300 143 and ETS 300 144 signalling model.

The document is also relevant where the same abstract test logic is reused for terminals that provide one or two 64 kbit/s digital channels, including non-ISDN videotelephony equipment that can support the required signalling behaviour.

Which standards are used with SIST I-ETS 300 763-2 E1:2003?

• ETS 300 143 - provides the in-band signalling procedures for audiovisual terminals using digital channels up to 2 048 kbit/s.
• ETS 300 144 - provides the frame structure for a 64 kbit/s to 1 920 kbit/s channel and the associated syntax for in-band signalling.
• ISO/IEC 9646 Parts 1 to 7 - provides the conformance testing methodology and framework used for TTCN-based test development.
• CCITT Recommendation G.711 - provides the PCM voice coding referenced for audio modes in the PIXIT and test method.
• CCITT Recommendation G.722 - provides the 7 kHz audio-coding reference used in mode-forcing questions.
• ITU-T Recommendation H.261 - provides the video codec reference and the CIF and QCIF picture formats used in the document.
• Part 1 of the multipart I-ETS - provides the Test Suite Structure and Test Purposes.
• Part 3 of the multipart I-ETS - provides the Protocol Implementation Conformance Statement (PICS) proforma.

What does the SIST I-ETS 300 763-2 E1:2003 document contain?

The document contains a test method description with a multiparty configuration figure, a BAS filtering model, a naming convention, and a split between single-channel and two-channel test groups. It also contains the test suite structure list and diagram, which show how capability, valid behaviour, and invalid behaviour tests are organized.

Annex A contains a PIXIT table with implementation questions about frame alignment, SBE capability, mode forcing, call initiation, and NS-Cap-related values. Annex B contains the ATS in both TTCN.GR and TTCN.MP forms, and notes that the graphical form takes precedence if there is an interpretation conflict. Annex C lists background references used to support the testing model and signalling context.

SLOVENSKI STANDARD
01-december-2003
Digitalno omrežje z integriranimi storitvami (ISDN) – Preskušanje znotrajpasovne
signalizacije pri avdiovizualnih storitvah – 2. del: Abstraktni preskušalni niz (ATS)
in dodatna informacija za preskušanje delne izvedbe protokola (PIXIT) – Proforma
specifikacija
Integrated Services Digital Network (ISDN); Audiovisual services in-band signalling
testing; Part 2: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra
Information for Testing (PIXIT) proforma specification
Ta slovenski standard je istoveten z: I-ETS 300 763-2 Edition 1
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
33.160.60 9HþSUHGVWDYQLPXOWLPHGLMVNL Multimedia systems and
VLVWHPLLQRSUHPD]D teleconferencing equipment
WHOHNRQIHUHQFH
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERIM
EUROPEAN I-ETS 300 763-2
TELECOMMUNICATION November 1997
STANDARD
Source: MTA Reference: DI/MTA-004120-2
Formerly: DI/TE-04120-2
ICS: 33.020
Key words: ATS, audio, inband, ISDN, PIXIT, testing, video
Integrated Services Digital Network (ISDN);
Audiovisual services in-band signalling testing;
Part 2: Abstract Test Suite (ATS) and partial
Protocol Implementation eXtra Information for Testing (PIXIT)
proforma specification
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1997. All rights reserved.

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I-ETS 300 763-2: November 1997
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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I-ETS 300 763-2: November 1997
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions and abbreviations .8
3.1 Definitions .8
3.2 Abbreviations .8
4 Introductory notes.9
4.1 Multiparty testing method.9
4.1.1 Sequencing and control of test components .9
4.2 Diagram of test method and test components.10
4.3 Description of PCOs .10
4.3.1 Description of higher layer PCO - received events .10
4.3.2 Pseudo code description of PCO operation - received events.11
4.3.3 Description of higher layer PCO operation - transmitted events .11
4.4 Naming convention .12
4.5 Audio and video signal content and coding .12
4.6 Description of D-channel activity.13
5 Test Suite Structure.13
5.1 Test Suite Structure - listing of test groups.13
5.2 Test Suite Structure - diagram.15
Annex A (normative): Partial PIXIT proforma.16
Annex B (normative): Abstract Test Suite in TTCN graphical form.17
B.1 The TTCN Graphical form (TTCN.GR) .17
B.2 The TTCN Machine Processable form (TTCN.MP) .17
Annex C (informative): Bibliography.18
History.19

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I-ETS 300 763-2: November 1997
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I-ETS 300 763-2: November 1997
Foreword
This Interim European Telecommunication Standard (I-ETS) has been produced by the Terminal
Equipment (TE) Technical Committee and approved by Multimedia Terminals and Applications (MTA)
Project of the European Telecommunications Standards Institute (ETSI).
An ETSI standard may be given I-ETS status either because it is regarded as a provisional solution ahead
of a more advanced standard, or because it is immature and requires a "trial period". The life of an I-ETS
is limited to three years after which it can be converted into an ETS, have its life extended for a further two
years, be replaced by a new version, or be withdrawn.
This is part 2 of a multipart standard covering "Integrated Services Digital Network (ISDN); Audiovisual
services in-band signalling testing", as described below:
Part 1: "Test Suite Structure and Test Purpose (TSS & TP) specification";
Part 2: "Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for
Testing (PIXIT) proforma";
Part 3: "Protocol Implementation Conformance Statement (PICS) proforma specification".
Proposed announcement date
Date of adoption: 24 October 1997
Date of latest announcement of this I-ETS (doa): 28 February 1998

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I-ETS 300 763-2: November 1997
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I-ETS 300 763-2: November 1997
1 Scope
This Interim European Telecommunication Standard (I-ETS) is part 2 of a three part I-ETS dealing with
conformance testing of Integrated Services Digital Network (ISDN) Videotelephony terminals. Part 1
contains the Test Suite Structure and Test Purposes (TSS & TP) and part 3 contains the Protocol
Implementation Conformance Statement (PICS) proforma.
This I-ETS contains the Abstract Test Suite (ATS) for conformance testing the in-band signalling aspects
of an ISDN Videotelephony terminal which uses one or two B-channels, and which implements the frame
structure and associated syntax as specified in ETS 300 144 [2] and the in-band signalling procedures as
specified in ETS 300 143 [1]. A partial Protocol Implementation eXtra Information for Testing (PIXIT)
Proforma is also included in this I-ETS. No testing of data commands or applications is included among
the tests. Test purposes for signal content of the B-channel are included in part 2 of the I-ETS but no
corresponding test cases have been included. Restricted network operation is outside the scope of this
I-ETS.
It may be possible to use this ATS in order to test a non-ISDN Videotelephony terminal, providing it
provides one or two 64 kbit/s digital channels for transmission. It may also be possible to use the majority
of these test purposes to test in-band signalling implementations according to ETS 300 143 [1] and
ETS 300 144 [2] using single or multiple channels up to 1 920 kbit/s.
2 Normative references
This I-ETS incorporates by dated and undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this I-ETS only when incorporated in it by amendment or revision. For undated references the
latest edition of the publication referred to applies.
[1] ETS 300 143 (1994): "Integrated Services Digital Network (ISDN); Audiovisual
services Inband signalling procedures for audiovisual terminals using digital
channels up to 2 048 kbit/s".
[2] ETS 300 144 (1996): "Integrated Services Digital Network (ISDN); Audiovisual
services, Frame structure for a 64 kbit/s to 1 920 kbit/s channel and associated
syntax for inband signalling".
[3] Reserved.
[4] ISO/IEC 9646 Parts 1 to 7: "Information technology - Open Systems
Interconnection - Conformance testing methodology and framework".
[5] CCITT Recommendation G.711 (1988): "Pulse code modulation (PCM) of voice
frequencies".
[6] CCITT Recommendation G.722 (1988): "7 KHz audio-coding within 64 kbit/s".
[7] Reserved.
[8] Reserved.
[9] ITU-T Recommendation H.261 (1993): "Video codec for audiovisual services at
p x 64 kbit/s".
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I-ETS 300 763-2: November 1997
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this I-ETS, the following definitions apply:
NOTE: In addition to the definitions shown in this subclause, the definitions in
ISO/IEC 9646 [4] also apply.
additional channel: The second or subsequent channels established in a videophone call.
bit-rate allocation signal: Bit position within the frame structure to transmit commands, control and
indication signals, capabilities.
capability marker; cap marker: The first code in a capability set.
capability set; cap set: A sequence of capability codes started by the capability marker code.
ECS channel: Optional 800 kbit/s channel for use in encryption.
initial channel: The first channel established in a videophone call.
mode 0F: Transmission mode in which the initial channel contains framing, and 7-bit
CCITT Recommendation G.711 [5] audio signal is being transmitted.
mode 0U: Transmission mode in which the initial channel does not contain framing, and 8-bit
CCITT Recommendation G.711 [5] audio signal is being transmitted.
remote terminal: The terminal with which the Implementation Under Test (IUT) is communicating, i.e. the
test tool.
3.2 Abbreviations
For the purposes of this I-ETS, the following abbreviations apply:
ASP Abstract Service Primitive
ATS Abstract Test Suite
BAS Bit rate Allocation Signal
C&I Control and Indication
cap capability
CIF Common Intermediate Format (picture format defined in ITU-T
Recommendation H.261 [9])
CP Coordination Point
CRC Cyclic Redundancy Check
CTP Combined Test Purpose
ECS Encryption Control Signal
FAS Frame Alignment Signal
ISDN Integrated Services Digital Network
IUT Implementation Under Test
LCO Loopback Command "Loop off request"
LSD Low Speed data
MBE Multiple Byte Extension
MCU Multipoint Conference Unit
MLP Multi Layer Protocol
MPI Minimum Picture Interval
MTC Master Test Component
PCO Point of Control and Observation
PDU Protocol Data Unit
PICS Protocol Implementation Conformance Statement
PIXIT Protocol Implementation eXtra Information for Testing
PTC Parallel Test Component
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I-ETS 300 763-2: November 1997
QCIF Quarter Common Intermidiate Format (picture format defined in
ITU-T Recommendation H.261 [9])
SBE Single Byte Extension
SC Service Channel
TP Test Purpose(s)
TSS Test Suite Structure
TTCN Tree & Tabular Combined Notation
4 Introductory notes
This second part of the multipart I-ETS contains the Abstract Test Suite (ATS) used in conformance
testing of Videotelephony in-band signalling procedures. The corresponding test purposes are defined in
part 1. The test cases are derived from the combined test purposes found in clauses 9 and 10 of part 1. A
PICS proforma, part 3 of this I-ETS, and a partial PIXIT proforma, an annex to this part 2, are referred to
by the ATS.
4.1 Multiparty testing method
This abstract test suite describes the testing specifications for testing in-band signalling in ISDN
Videotelephony terminals using one or two B-channels. Testing activity will take place on the D-channel
(for call control) and on one or both B-channels. Consequently, a multiparty, or concurrent testing method
is necessary.
The test method employed makes use of a Master Test Component (MTC), or controller, and three
Parallel Test Components (PTCs), or slaves: one each for the D-channel and the two B-channels. No
actual testing is performed by the MTC, as all Points of Control and Observation (PCO) are on the PTCs.
Each PTC uses a remote test method in its testing, as described in ISO/IEC 9646 [4].
4.1.1 Sequencing and control of test components
There are communication paths between the MTC and each PTC, and also between the two B-channel
PTCs, for transmission of co-ordination messages during test execution. The MTC handles all scheduling
of test components, with the three PTCs running largely independent of each other. There is therefore a
minimal need for co-ordination messages to be passed between the PTCs and the MTC during a test
case. In a real implementation of this ATS, it may not be possible to have four individual test scripts
running on a test tool; it may therefore be necessary to combine the functions of the MTC and the
D-channel PTC. This should be possible, if some care is taken. Likewise, the actual co-ordination
message contents and the control structure may need to be changed according to test tool
implementation. The final control structure used should not, however, change the sequence of test events
specified in these abstract test cases.
The sequence of events at the start of testing the majority of test cases on one B-channel is as follows:
- all test components start simultaneously;
- B-channel and D-channel test components wait for co-ordination message from MTC;
- MTC sends message to D-channel requesting it to initiate a call;
- D-channel sends message to MTC when B-channel is established and waits for next message;
- MTC sends message to B-channel to cause it to start the test activity;
- MTC waits until B-channel test component has finished executing or a long timer has timed out
(B-channel has crashed);
- MTC sends message to D-channel to request clearing of B-channel;
- MTC waits until D-channel test script has finished.
As can be seen, most of the test cases are started with the B-channels being initiated by the test tool, not
the Implementation Under Test (IUT).

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I-ETS 300 763-2: November 1997
4.2 Diagram of test method and test components
Figure 1 shows a logical view of the complete configuration of the MTC, PTCs, and PCOs.
The Coordination Point relationships between the various components are also indicated.
TC_Master
MTC
CP_Master_D CP_Master_B1 CP_Master_B2
TC_D TC_B1 TC_B2
PTCs
IUT
CP_B1_B2
B1H B2H
D B1L B2L
PCOs
ASP Filter ASP Filter
D-channel
B-channels
s/t bus
TESTER
Figure 1: Testing configuration
4.3 Description of PCOs
The test method adopted employs separate parallel test components for the D-channel and two
B-channels. Each B-channel test component has two Points of Control and Observation (PCOs). These
are the points at which the IUT's behaviour is visible to the test script running on a test tool.
In ETS 300 143 [1] and ETS 300 144 [2], there is no explicit layered structure for the in-band signalling
protocol. However, there is an implicitly defined structure: a lower layer dealing with frame and multiframe
structure, bit encoding of Bit rate Allocation Signal (BAS) codes and their corresponding
Cyclic Redundancy Check (CRC) codes, bit position of audio, video and data within a frame etc., and a
higher layer dealing with the various sequences and procedures which make use of BAS codes to control
the communication.
4.3.1 Description of higher layer PCO - received events
Sets of BAS codes are passed in Abstract Service Primitives (ASPs), through the higher layer PCO to the
test script running on the tester. As the same BAS command codes are received continuously during
normal operation of in-band signalling, a filtering operation needs to be performed in order to decide which
BAS codes to pass up to the test script in an ASP. Without
...